Immunotherapy company Scancell Holdings plc (AIM: SCLP) revealed on Monday that it has received clearance from the U.S. Food and Drug Administration for its Investigational New Drug application, enabling a global registrational Phase 3 trial of its iSCIB1+ Immunobody in advanced melanoma. A trial is planned to start in 2026, with progression free survival agreed as the surrogate endpoint.

Clearance follows completion of the 140-patient Phase 2 SCOPE study evaluating SCIB1 and iSCIB1+ in combination with nivolumab plus ipilimumab in previously untreated unresectable stage IIIB/IV melanoma. Data identified a selection marker to enrich the Phase 3 population and supported advancement of iSCIB1+, administered needle-free intramuscularly, in patients with selected HLA alleles representing around 80% of melanoma patients.

Updated results from the target population showed progression free survival of 74% at 16 months, compared with 50% at 11.5 months reported for ipilimumab plus nivolumab alone, the current standard of care. Interim analysis indicates a 24 percentage point improvement in progression free survival versus real-world standard of care and historic controls, with consistent benefit across key subgroups including PD-L1 low and BRAF wildtype patients.

The company said the Phase 2 data demonstrate potential for iSCIB1+ to redefine standard of care in advanced melanoma and support progression to a registrational Phase 3 programme.